Tireless (13)
'tireless' is the definition.
(synonyms)
This is all the clue.
(Other definitions for indefatigable that I've seen before include "with no end of energy" , "Assiduous" , "Persisting tirelessly" , "Relentless" , "Unremitting" .)
'tireless' is the definition.
(synonyms)
This is all the clue.
(Another definition for inexhaustible that I've seen is " Tireless".)